1. Field of the Invention
The present invention relates generally to apparatus for separating flat products from a pile of flat products, and particularly to an apparatus for separating flat products from a pile of flat products, the apparatus including a sucker mechanism having a movable sucker tube.
2. Background Information
In the technology of building books, including booklets, magazines, periodicals, and the like, the use of collating systems is well known. These systems typically have a transporting device on which individual flat products, such as signatures or sheets, are gathered to build a book-block set, which then is finished and bound. Typically, a number of feeders are arranged along the transporting device, each of the hoppers comprising a feeding mechanism for feeding an individual flat product from a pile of signatures onto the transporting device, in order to gradually build up the book-block set or to insert a supplement sheet into a pocket of a pocket feeder or into a newspaper arranged in the pocket. Such feeding mechanisms typically employ a sheet-separating device for separating a sheet or other single flat product from a pile of flat products which is arranged in each hopper. The single flat products are drawn from the pile at its bottom end.
A sheet-separating device of this kind is described, for example, in U.S. Pat. No. 3,988,016. This document describes a high-speed paper inserting apparatus for insertion of supplements into newspapers. The inserts are placed to form a stack and a vacuum gripping member grips the lowermost insert from the stack and carries it to a pair of nip rollers which transport the insert to an opened newspaper. A single sheet requires a different sucker stroke than a 120 page or pre-inserted section. The different sucker motion requirements are due to the way the sheets or sections have to be positioned and controlled for proper singulation. Generally, the bottom of the stack of heavy sections is elevated to eliminate followers. This is accomplished by repositioning the lift hook and restrictors. When these adjustments are made the vacuum cup motion must be changed. To raise the sucker motion so that it properly engages the pile requires the sucker bar to stroke through a greater angle. In U.S. Pat. No. 6,168,148 an adjustable sucker mechanism having an upper and a lower part is coupled to a central lever. The central lever is rotatable about an axis extending through the central lever. The adjustment can be accomplished by moving the axis along the central lever.
The present invention provides an apparatus for separating flat products from a pile of flat products, the apparatus including a sucker mechanism including:
a sucker tube having a first and a second end;
at least one sucker cup coupled to the sucker tube at the first end of the sucker tube; and
a vacuum device for providing a vacuum, the vacuum device being coupled to the sucker tube at the second end of the sucker tube;
wherein the second end of the sucker tube is movably received in the vacuum device so as to enable the at least one sucker cup to be variably positioned relative to the pile of flat products.
The sucker mechanism may be pivotable relative to the pile of flat products so as to enable the sucker cup to move to engage a bottommost flat product from the pile of flat products.
The vacuum device may define a bore therein, the second end of the sucker tube being slidably received in the bore.
The sucker mechanism may include a slide for positioning the sucker tube, the slide being coupled to the first end of the sucker tube and slidably disposed relative to the vacuum device.
The slide may be slidably disposed on-the vacuum device. A fixing device may be provided for holding the slide in a predetermined position. The fixing device may include a screw.
The vacuum device may include a vacuum inlet for generating a vacuum in the vacuum device.
A sucker bar may be provided, with the vacuum device being disposed on the sucker bar.
The sucker mechanism may also include:
a second sucker tube having a respective first and a second end;
a second sucker cup coupled to the second sucker tube at the respective first end of the second sucker tube; and
a second vacuum device for providing a vacuum, the second vacuum device being coupled to the second sucker tube at the respective second end of the second sucker tube;
wherein the respective second end of the second sucker tube is movably disposed in the second vacuum device so as to enable the second sucker cup to be variably positioned relative to the pile of flat products independently of the sucker cup.
The sucker mechanism may include a slide for positioning the sucker tube and the second sucker tube, the slide being coupled to the first end of the sucker tube and the first end of the second sucker tube and slidably disposed relative to the vacuum device.
The slide may be slidably disposed on the vacuum device.
The present invention also provides a method for separating flat products from a pile of flat products, the method including:
providing a sucker mechanism including a sucker tube having a first and a second end, a sucker cup coupled to the sucker tube at the first end of the sucker tube, and a vacuum device for providing a vacuum, the vacuum device being coupled to the sucker tube at the second end of the sucker tube, the sucker tube being movably disposed in the vacuum device; and
varying a position of the sucker cup relative to the pile of flat products by moving the sucker tube relative to the vacuum device.
The apparatus and method according to the present invention enable the sucker cups to be adjusted individually or in groups so as to adjust the respective sucker strokes to the type of flat product being separated from the pile in a feeder hopper.